1. Field
The present disclosure generally relates to composite columnar structures, and deals more particularly with a hybrid composite tubular strut internally reinforced to better resist axial compression loads.
2. Background
Columnar structures formed of composites are used in a variety of applications because of their favorable strength-to-weight ratio. For example, composite tubular struts may be used in the aerospace industry as a support or brace for transferring loads in either direction along the longitudinal axis of the strut, thus placing the strut in either compression or tension. Fittings on the ends of the strut provide additional strength at the points of attachment of the strut to a structure.
The tubular struts mentioned above may be fabricated from fiber reinforced resin laminates. Such laminates may exhibit greater load carrying ability when placed in tension than when placed in compression. This is because the compressive strength of the resin is generally less than its tensile strength. Consequently, in order to meet performance specifications, it may be necessary to over-size the strut to carry a specified level of compression loading. Over-sizing the strut, however, may add cost and/or undesired weight to a vehicle or other structure to which the strut is attached.
Accordingly, there is a need for a composite columnar structure that exhibits improved ability to carry compression loads. There is also a need for a cost effective method of making a columnar structure with improved compression load carrying ability that adds little or no weight to the structure.